Performance and Reliability of 4 Mb eFLASH Memory Array Featuring 28 nm Split-Gate Cell with HKMG Select Transistor

This paper presents the characterization and reliability results achieved on 1.8 V 4 Mb flash array built around 3rd generation Embedded SuperFlash® (ESF3) memory cell featuring high-k metal gate (HKMG) select transistor and embedded into Low-Power 28 nm CMOS HKMG technology with gate-first architecture. Endurance shows better performance in terms of erase degradation as compared to prior technology nodes with poly-SiON select transistor. This improvement is attributed to HKMG-related process integration scheme allowing to reduce the effect of the CMOS baseline on tunnel oxide quality. Excellent program-erase performance, program disturb windows and data retention capability are observed.